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dbsrch

Database search

dbsrch(mp, n, pop = NULL)

What a match found by trawling a database is worth. np is the bound of the second National Research Council report: the match probability times the number of profiles searched. any is the exact chance of at least one chance match among that many unrelated profiles, never above np. post takes the other view (Balding and Donnelly): everyone else in the database was excluded, so among pop possible sources with equal prior the matching person’s probability of being the source goes up, not down. See proof("dbsrch").

mp

The profile match probability: one number above 0 and at most 1.

n

The number of profiles searched, the match included.

pop

NULL, or the number of possible sources, at least n.

A named numeric vector: np, any and, when pop is given, post.

Balding, D. J. and Donnelly, P. (1996). Evaluating DNA profile evidence when the suspect is identified through a database search. Journal of Forensic Sciences, 41(4), 603-607.

dbsrch(mp = 1e-9, n = 5e6, pop = 3e7)

Generated from the R help page: dbsrch in the R reference.